class Solution(object):
    def fairCandySwap(self, aliceSizes, bobSizes):
        """
        :type aliceSizes: List[int]
        :type bobSizes: List[int]
        :rtype: List[int]
        """
        t = (sum(aliceSizes) - sum(bobSizes)) // 2
        b = set(bobSizes)
        for a in aliceSizes:
            if a - t in b:
                return [a, a - t]